The avermectins (formerly identified as C-076 compounds) are a family of macrocyclic lactones which have been found to be highly effective against a broad range of pests which infest and are an annoyance to plants and animals. The compounds are active against ectoparasites and endoparasites of domestic animals, including food and pet animals and also man. In addition, the compounds are very effective against arthroped pests which affect plants while in storage or while growing either in the aerial portion of the plant or from the soil in which they grow.
The avermectin compounds are isolated from the fermentation broth of a microorganism, Streptomyces avermitilis. The isolation and purification of such compounds is described in U.S. Pat. No. 4,310,519 issued Jan. 12, 1982. Several derivatives of the avermectin compounds have been prepared and such derivatives have also been found to behave synergistically in the instant combination. Specifically the 22,23-dihydro derivatives and the monosaccharide derivatives are synergized by the instant combination.
Compounds which are somewhat related to the avermectins, but which have significant chemical differences, are the milbemycins. Such compounds have been found to be active miticides and insecticides. In tests the ovicidal activity of such compounds has been seen to be enhanced by the addition of machine oil, however, such activity has been demonstrated to be significantly different from the instant synergistic activity againist the motile (active) stages of agricultural insect and mite pests. In addition, tests have shown that the milbemycin compounds, when used in the manner described herein actually have a reduced activity, that is, the combination of the milbemycin with oil has less activity than the milbemycin alone.